title: Mutants blocked in streptomycin production in Streptomyces griseus - the role of A-factor.
abstract: Ninety-five streptomycin-nonproducing mutants derived from Streptomyces griseus FT-1 by UV-irradiation could be classified into major two classes by cosynthesis tests. Class I mutants (42 strains) were mutants blocked in the pathway of streptomycin biosynthesis while class II mutants (49 strains) required a factor for streptomycin biosynthesis which was excreted by the parental or class I mutant strains. The factor could be replaced by synthetic A-factor (2S-isocapryloyl-3-S-hydroxymethyl-gamma-butyrolactone) which restored both streptomycin biosynthesis and spore formation in the class II mutants. A-Factor deficient mutants were obtained from several strains of S. griseus and S. bikiniensis at high frequency by treatment with acridine orange or incubation at high temperature. A mutant whose streptomycin biosynthesis was independent of A-factor deficiency was found. The production of A-factor was distributed among various species of actinomycetes.
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives; D002851:Chromatography, High Pressure Liquid; D003470:Culture Media; D006133:Growth Substances / Q000378:metabolism*; D006358:Hot Temperature; D009154:Mutation; D013305:Streptomyces griseus / Q000235:genetics* / Q000378:metabolism; D013307:Streptomycin / Q000096:biosynthesis*; D013997:Time Factors
chemical_list: D003470:Culture Media; D006133:Growth Substances; C025035:A-factor (Streptomyces); D015107:4-Butyrolactone; D013307:Streptomycin